i know one or 2 butchers and none of them seem short of a bob or 2. i think it would be easy enough to do and i deffinatly think you would need to have another experienced butcher with you to start with until you get use to things, mainly to make sure you start of providing a decent quality of meat. as with everything once you have gained a little experience then your good to go it on your own if needed.
shop location would be impotant, to set up from scratch would be bloody expensive.